Method for creping paper



Oct. 28, 1947. F, P, WOOD V2,429,706

METHOD FOR CREPING PAPER Original Filed June 26, 1944 5 Sheets- Sheet 1 20 faz/72% y,

loef. 29,1947. F. P. man 2,429,796

` METHOD FOR CREFING PAPER joriginal Filed June 2e, 1944 45 sheets-sheet 2 I ZM/97ML Oct. 28, v1947.- F. P. woon METHOD FORv CREFING PAPER Original Filed June 26, 1944 5 Sheets-Sheet 3 Oct. v28, 1947. F. P. WOD 2,429,706

' METHOD FOR CREPING PAPER v original Filed June 21e, 1944 5 sheets-sheet 4 i' e i E E E i E E i i i s Oct. 28, 1947. F. P. wooD METHODFOR CREPING PAPER v Original Filed June 26, 1944 5 sheets-sheet` 5 Patented oci. 12s,. 1947 A2,429,706

e' UNITED STATES PATENT OFFICE METHOD FOR CREPING PAPER Frederick P. Wood, Adrian, Mich.; assignmto Simplex Paper Corporation', Adrian, Mich,v a corporation of Michigan Original application June 26, 1944. Serial No.

542,224. Divided and this application January y 1 The method of this invention involves the creping of paper intransit, while being continuously fed from a roll, by means of concurrently traveling crimper bars which in close succession engage the paper surface along lines of spaced contactl points which progressively drawY closer together as the paper advances, thereby imparting minute crimps or indentations in the surface whichrender the completed strip elastic in all directions. This result can be attained either by an embossing or indenting action on the paper web or by a pinching action which produces minute folds, with a resultant narrowing of the web and both of these variations in the operation are deemed to be within the range of the present invention since the active crimper bars are substantially the same in each case while a mere variation in the backing which supports the paper web will modify the nature of the compressive action Iimparted to the paper surface with a resultant difference in the crimping.

Further objects and details will appear from the following specification in conjunction with the accompanying drawings wherein:

Figure 1 is a side elevation, partly broken away, of one type of machine adapted to operate in conformity with the indenting principle of the present invention;

Figs. 2, 3 and 4 are details of one of the crimper bars showing the positions it progressively assumes, and taken respectively on lines 2, 3vand 4 of Fig. 1; e

Figs. 5 and 6 are enlargeddetails of a portion of one of the crimper bars showing the teeth along its acting face in open and contracted relation respectively;

Fig. 7 is an end elevation of the machine looking toward the rear end of the machine into which the paper is fed;

Fig. 8 is a perspective detail of the connections for the ends of the crimper bars;

Fig. 9 is a side elevation of a modified form of the indenting type of machine;

Figs. 10 and 11 are enlarged details of a type 45 of crimper bar for use on the machine of Fig. 9

Figs. .12 and 13 are side elevations of two machines of modified form adapted to pinch the paper surface in the formation of minute plaits; and

Fig. 14 is a perspective View of the backing plate of the machine of Fig. 13.

The machine of Fig, 1 employs a backing drum 20 having a facing layer 2| of relatively soft yielding material such as rubber over which the paper web P is fed by the rotation of the drum which 18, 1945, Serial No. 571,915

3 Claims. (Cl. 154-33.05)

2 is carried by a shaft 22 power driven in any suitable manner, as for instance by worm gearing 23.

The paper web is fed from under a roll 24 in advance of the forward end of the drum and is carried over and around the soft surface thereof Vso thatv contact is maintained throughout about 180. 'I'he paper is progressively compressed into the soft surface of the drum by a multiplicity of closely spaced flexible crimper bars 25 formed of relatively thin flexible steel or the like, which bars at their ends terminate in loops 26 connected by shackles 21 with the links of a pair of spaced endless chains 28. The chains are carried around front and rear pairs of lower sprockets 29 and 30 respectively, the front sprockets being mounted upon a shaft 3| and the rear sprockets uponl a rear shaft |32. The lower sprockets cooperate with the front and rear pairs of upper sprockets 33 and 34 mounted upon shafts 35 and 36 which are journalled in any suitable manner. v

Certain of the sprockets as, for instance, 'the rear sprockets 30 constitutelthe driving sprockets for imparting travel to the endless chains, the lower turns of which travel in arcuately converging relation to the surface of the drum and are slidable within guide members 31 mountedupon the frame of the machine.

, face at the center, and as the chains advance in registering surface speed with the drum, the crimper bars will be progressively straightened out and will thereby progressively increase their surface contact with the paper web lying smoothly around the drum surface.

The front end 40 of the fixed shoe is looped upwardly to find support upon theshaft 3| while the rear end 4| ris likewise looped upwardly to find support upon the shaft 32. Except for the looped ends. which simply serve as hangers, the shoe (or shoes) extends from front to rear of the backing plate, i. e. the peripheral surface of thev drum, and

in close proximity to its longitudinal center, the spacing being sufficient only to permit the relatively thin crimper bars and the paper web to travel through the space thus afforded, with the crimper k.bars inprogressivelyv increasing contact throughoutv with the upper surface of the paper web and progressively increasing the area toing surface of the drum.

As the lower turns ofthe chains pass around and under the forward lower sprockets, the. middle of each crimper bar will in turn pass under the ilxed shoe so that as the chains advance, the crimper `bars will initially be bowed downwardly inthe center to the maximum extent, .and therel after, as the chains continue to advance, the convergency of the chains running-through the guides 31 toward the surface of the drum will cause the crimper bars to progressively straighten out as indicatedinFigs. 2, 3, and 4, while at the the paper surface which as it is embossed will by degrees draw'in or narrow itself as a result of thev -4 loopsfand shackles'of the character first describedand the'chains are mounted and driven in thesame manner as in the case of the machine 'of Fig. l. In this instance also the paper is stripped away by a doctor blade 48 which is curved to conform to the curvature of the backing plate at its .discharge end.

The machines of Figs. 12 and 13 employ crimper bars and mountings therefor which are substantially identical withA those previously described, but instead of a, backing drum which rotates with the advancing crimper bars to establish a progressively'increasing contact therewith, I employ a nxed backing plate having a surface contour which .is complementary to the contour collectively' presentedfbyv the series of crimper bars vwhile actively engaging the paper, so that the same time establishing progressive contact withl indenting ofitssurface but without anyA tendency y to rupturesince the compressive embossure progresses gradually` from the center toward the edges and by degrees which do not exceed the capacity of the paper web to withstand rupture.

The crimping is effected by teeth of the character indicated in Figs. 5 and 6. Each of the crimper bars is of sufficient thickness to permit the formation, in its under face, of teeth or bosses 42, the tips of which compressively vengage the upper surface of the paper web and press the same into the lsurface of the drum. In the bowed or flexed condition shown in Fig. 5, the tips of the teeth will be spread apart to a greater degree than when' the crimper bar is straightenedjas in Fig. 6, so that as the paper web advances, the

teeth, in progressively increasing` number, will make contact with the surface of the paper concurrently with its forward travel through the machine.

A doctor blade 43 serves to strip the paper from paper surface will be subjected to an overall compressive contact with the crimpers as itv moves v thus draw in the paperfrcm the edges of the the side ofthe drum after which the paper web y is wound up or otherwise disposed of.

In Figs.'912 I have showna modified form of construction embodying the same generalprincip'le'of operation, in which, however, the relative configuration of the drum and the crimper bars is reversed as compared with the arrangement vfirst' described; f

In this construction, the rubber surfaceddrum 44 is of barrel shape being bulged or convexly yrounded outwardly around its center.v The crimp- I er bars 45 will initially lie dat and make tangent contact with the center of the drum surface and will be progressively flexed downwardly as they advance over and around the drumvuntil at the discharge side they will be bO/Wed or arched to the fullest extent so that as the paper is`fed lforward- ,web in the formation of a multiplicity of folds or plaits running lengthwise of the paper web.

' `In` order to thus maintain extended surface contact between the paper and the crimper bars,

I provide a backing plate which may be'congured like the plate 49of Fig.. 1 2 or like the plate y5i] of Figs. 13 and'14. The plate 49 coacts with crimper bars, which, likev those of the machine ofFig. 1, `are linitially bowed downwardly to the maximum degree and are serrated by teeth 5|l which will be distended or spread apart to the maximum degree at the entering end 52 of the backing plate, which is trough-shaped to maximum depth at 'this end, but which gradually flattens out toward its discharging end 53 to conform to the flattening down of thecrimper bars as they travel above its surface and compress thepaper. webr thereon and maintain overall compressive surface contact therewith from end to end of they backing plate.

With thetoothed faces of the crimper bars'thus incompressive engagement withthe paper surly under the crimper bars, it will be carried up' Aand over the bulging surface Iof theA drum,and its edges progressively flexed downwardly in greater and greater degree as the area of contact between the crimper bars and the yielding drum surface'v is progressively extended. K

In this instance I have shown crimper bars 46 formed of comparatively thin strips of 'flexiblel steel or the like which are corrugated to afford downwardly facing teeth or bosses 46 on their `under faces and in this instance, in viewgof the fact that the crimper bars will be flexed down.

wardly as they advance, the teeth will be' presented on the concave faces of the crimperbars and hence will contract as the concavity ofthe -bars increases due to the progressive flexure.

The ends ofthe bars are secured to chains 41 byi face at all points, the teeth will gradually contract as 'the crimper barsljare straightened out,

and this will have the yeect of progressively l drawing in the paper toward the center, in the 4formation of minute folds or plaits which will gradually close up as the crimper teeth contract in the straightening out ofthe crimper bar s.

In the machine of Figs. 13 and 14 the crimper bars and their mountings are arranged in amanner identical with that of the machine of Fig. 9, but in lieu of a rotating barrel shaped drum, I employ the'iixed backing plate lill` which is flat at the end 54 where the paper venters and which is progressively arched upwardly in greater and greater degree,` after the manner of an inverted trough, to conform to the progressively increasing iiexure of the crimperbars which present their toothed acting faces downwardly ,to effect the closing or contracting of the teeth as the flexure of the crimper bars increases. The crimping or plaiting action, however, is substantially the same as that of the machine of Fig. l2, and it will bev a widely extended area. In `either case the paper web will be drawn or fed through the machine by the pinching action of the advancing teeth, so

that as the teeth contract, the web throughout will necessarily be under extended contact thereof the paper web will accrue gradually so that excessive and abrupt stresses which might tend to rupture the web are avoided. At the same time the feeding speed may be maintained at a high rate by the pull Vofthe advancing crimper bars without subjecting the paper, web to feeding tension which, if applied, might tend to straightwith, but the drawing in and resultant narrowing r disclosed in my application filed June 26, 1944,

Serial No. 542,224, now Patent No. 2,393,672, dated January 29, 1946 of which this case is a dil vision. l

I claim: 1. The method of creping a web of paper traveling over a supporting bed which consists in initially inwardly directing against the medial surface of the webA only lat points closely spaced longitudinally ofthe paper a plurality of closely spaced pressure contact points and thus indenting the medial area. of the paper surface, and then progressively laterally increasing the acting number of such contacts and thus subjecting a. laterally increasing area of the paper to indenture without displacing the longitudinal relation of said pressure contacts to the paper surface, and concurrently progressively reducing the transverse spacing of said pressure contact points as the paper advances.

2. The method of creping a web of paper traveling over a supporting bed which consists in initially creping the paper only at the center at 'closely Ispaced points longitudinally of the web by a pinching action to form minute longitudinal folds with a resultant narrowing of the web and by simultaneously indenting the paper into a soft supporting surface to form transverse rows of indentations .at said closely spaced points longitudinally of the web and then progressively increasing the creping action and the indenture uniformly transversely of the web until the entire surface of the web of paper is creped, thereby rendering the completed web of paperelastic in all directions. Y, y v

3. The method of creping a web of paper traveling over a supporting bed which consists in initiallyl inwardly directing only against the medial area ofthe surface of the web at points -closely spaced longitudinally of the paper a lplurality of pressure contact points to pinch the web between them and form minute longitudinal folds with the resultant `narrowing of the web and simultaneouslydndenting the web to form transverse rows of indentations at said closely spaced points longitudinally of the web, and then progressively laterally increasing-the active number of such pressure contact points and thus subjecting a,

laterally increasing areal of the paper to said pinching action and indenture without displacing the longitudinal relation of the pressure contact points to the paper surface until the entire surface of the web of paper is creped, the pinching action and the indenture rendering the completed creped paper elastic in all directions.

FREDERICK P. WOOD.

REFERENCES CITED The following references are of record in the iile of this patent:

40 Number UNITED STATES PATENTS 

